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Splashpower Boasts Wireless Power
Sullivan writes "Maccentral is running a story on a startup called Splashpower that hopes to be able to wirelessly recharge all of our handheld devices. They have a working prototype that already recharges an iPod Mini and a cell phone. Now we can look forward to yet another way to get brain cancer."
I think this is a very cool device and have often wondered why more devices haven't come with wireless re-chargability (think electric toothbrushes). But I wonder about the efficiency of this method. Is it? And if it's not, how less efficient is it than direct contact recharging? As more and more gadgets and devices become rechargable technology this would seem to be more important. I don't know much about electronics at the engineering level, so any erudite replies would be appreciated.
This is probably how Tesla would have charged his iPod.
My first thought when reading this: Build it in to a desk and use it as your mouse pad. Then, you would never have to charge your wireless mouse. Sweet.
--Nycto
still, i'd like it if this became mainstream.
philo
No, but once (if) it gets built into phones, if you're away on a business trip and forget your cellphone charger you'll be glad the hotel provided a pad in your room.
My electric shaver recharges this way, and i've been wondering why we don't just have a pad that we can toss our electric gadgets onto for recharging.
My wish has been granted!
As for efficiency, I'll refer you to DansData, because he knows the answer to everything.
Your Answer Here
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o0t!
You forgot "clean all of the lint and crud out of the charging port" and "wiggle phone around so the contacts make good contact rather than just barely missing" in your description of the old method. You also may have forgotton "make sure that cord is at such an angle so as to facilitate minimal breakage after grabbbing and walking away without remembering to unplug it in the morning". :)
Yes they did prove it...at least my college physics prof did by using a hypothetical line 1 foot above your head carring an impossible amout of power (1 million volts or somthing silly like that). The magnetic field generated by the line was several orders of magnitude less than the magnetic field of the earth which you are exposed to at all times.
Also the cell phone brain cancer thing is becoming less and less likely.
Apple free since 1990!
So, they have created a device that recharges devices wirelessly, if you place the device on top of the pad.
My cell phone, my beard trimmer, and my toothbrush already recharge wirelessly... sure, I have to place them in their cradles and line up the contacts, but it's still approximately the same.
What is being offered here is a universal charger system. The rest of it is bells and whistles. What Splashpower needs to do is get the device producers to incorporate the hardware necessary for this, and to get hotels etc. to install the pads.
This is problematic, as stated in the article. Device-makers won't install the charging coil unless the infrastructure for charging is in place; establishments won't purchase the charging pads unless a sufficient amount of devices have the coil installed. There's just no ROI for a hotel chain to install these in their rooms and suites, and no reason for an end-user to purchase an enabled device if chargers aren't available.
Nice idea, but don't buy stock.
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
The efficiency is probably not at all bad; the magnetic field is short range and, in the absence of a receiver, the only thing in the magnetic circuit to absorb energy is the hysteresis of the inductor in the transmitter. Which, with modern ferrites, can be pretty small, unless of course they are using a purely air-cored system at the transmitter end, in which case it's tiny.
The huge potential benefit of this system is that it eliminates the second most unreliable part of electronic systems: connectors. Anyone who has worked at the sharp end of electronics knows that connectors suck, big time. Designs proliferate. There are far too many of them and they are far too unstandardised. And connectors designed to be repeatedly made and broken are the worst of the lot. Although the designs have come a long way (the fact that gigabit copper Ethernet connectors work is a small electronic miracle in itself) they are still the worst part of any system, after the batteries.
So here we have a system which if widely adopted allows most of the tiny connectors used in portable devices to disappear, and possibly reduces the demands on batteries because people will find recharging easier. Those are big pluses.
Panurge has posted for the last time. Thanks for the positive moderations.
I guess the prof's theoretical calculations don't explain why HVAC lines will make a fluorescent tube light up at a distance, yet Earth's magnetic field does nothing...
IMO, what we need is a single standard for power distribution that caters to the device, not dozens of adapters that are a slave to a single 120VAC standard.
Most small electric devices operate off of DC power, so no matter what, you have to have an adapter to convert AC power to DC. Since you have to have the adapter anyway, it doesn't really matter what DC voltage you go with, so you pick whatever's going to be cheapest for the situation. Consequently, we have all sorts of DC power requirements.
What might help the situation is for someone to come up with a standard for power outlets that use a standardized DC voltage in addition to AC. Or maybe a handful of voltages. Different contacts could provide your DC voltage(s), in conjunction with your AC voltage.
Device manufacturers could then target those standardized voltages and spend less money on adapters.
The "I'm getting cancer and my kids have ADD because of the powerlines in my house" crowd and their lawyers are going to have a field day with this!
Yeah ... especially when the attorneys (whose suits will still cost more than their laptops and cell phones) are typing away on their laptops using WiFi and mobile phones with Bluetooth!
Case ... dismissed!
The Luddites were ahead of their time.
Also, you're going to get less than .7 efficiency from the inductive recharger. The .7 efficiency on something like a toothbrush-charging stand assumes that the coils actually overlap slightly (know that little knob that the toothbrush rests on? It's actually part of the magnetic core that helps transmit the AC over). The electric field decreases with the square of distance. In one of those toothbrush chargers, the inductors are separated maybe by a millimeter of thin plastic. If you have... say a mousepad-sized recharging "station" to put all of your goodies onto, you might end up with distances of several inches from the charging coil to the pickup coil in the device you actually want to charge. Without having an actual "stand" like electric toothbrushes do, you aren't going to transmit much power. If you're going to have a stand, might as well have metal contacts, and forego the less efficient inductive method. The only reason why toothbrushes really do that is because they're often wet, and you put them in your mouth, so you wouldn't want metal contacts sticking out (my waterproof electric razor actually has metal contacts, you just wouldn't want to plug in the AC while it's wet).
Nothing says "unprofessional job" like wrinkles in your duct tape.
Why do people think radio waves when they hear "wireless"? Hmmm... it seems obvious to me that the trick is to induce a electric current with a magnet that is not strong enough to completely destroy the electronic components inside the device. This would work toward eliminating multiple adapters to recharge various devices and overloading wall sockets with adapters. They aren't saying that they are recharging the devices with a high power 2.4 Ghz signal. Duh.
7h3$3 4r3n'7 7h3 Ðr01Ð$ ¥0 4r3 £00|{1n9 f0r. M0v3 4£0n9. --OB1
But two questions: First, was it alternating current? And second, how much amperage was going through the line?
Just having 1,000,000 volts above your head means nothing if there's little amperage and it's a DC power source. Alternating currents cause electromagnetic fields to propogate, and large amounts of current causes them to be more powerful. This is why you can get a flourescent tube to light up when you stand underneath high power transmission lines - The electromagnetic field from them is inducted into the tube and there is still enough power to excite the mercury atoms. Last I checked the Earth's magnetic field couldn't do something like that...
I can see why the brain cancer/cell phone controversy exists - Basically you have a very, very powerful source of EM in a concentrated spot next to your ear. The problem is that nobody can seem to prove conclusively that it causes cell mutations.
-R
You're that guy from the TV commercials, aren't you? You know, the guy for whom straining spaghetti or wiping off a table or opening a jar are so incredibly difficult and frustrating that you have to swipe all your existing products off a tabletop with both hands and buy some special device to do it for you.
Splashpower is a really interesting company; a couple of students took developed a business plan for a competition. They won the competition and started the company off the back of it while they were still at university. They used an idea that they reasonably certain could be solved (they were both engineers) and started serious work once the funding was sorted out. They've received angel and venture funding.
Splashpads are quite interesting in that they are active devices. When you drop something onto the pad, there's some communication that goes on between the pad and the device. The pad delivers power to the right place on the pad to recharge that device, and only that place. You don't have to orientate the device correctly, and there's no contact made. You can have multiple devces recharging at once.
If you drop your keys onto the pad then they won't electrocute you when you pick them up. And they won't heat up. If you drop electronics that's not enabled onto the pad, then it won't get electrocuted either.
There is a chicken-and-egg problem. On the other hand, I would not be at all surprised to see at least one cell-phone manufacturer adopting their system, and the first step in widespread adoption is to get individual manufacturers to commit to it. They also have the advantage that past a certain penetration point it becomes a de facto standard.
There are several other competing companies. In my opinion the Splashpower system is one of the best and most likely to succeed providing they can move past initial adoption.
Re braincancer. Deeply, deeply unlikely. Worry about the X-rays emitted from your CRT first.